When aircraft land at most large airports today, they operate one or more of their main engines to power their ground travel as they taxi from a touchdown runway to an assigned terminal arrival gate. Although specific procedures may vary at different airports, most airport terminal gates are equipped with passenger loading bridges that are moved into place when an aircraft has arrived at the gate to provide a connection between the aircraft and the terminal. Currently, a loading bridge cannot be connected to an aircraft until the main engines powering the aircraft have been shut down, and it is safe to approach the aircraft. When the loading bridge has been connected to an aircraft door, usually the door closest to the forward or nose end of the aircraft, and the aircraft door have been opened, passengers and crew can leave the aircraft and walk to the terminal through the loading bridge. Loading bridges are designed to provide a pathway between an aircraft interior and an airport terminal building that shelters passengers and crew from the surrounding environment. While deplaning passengers are walking through a loading bridge to the terminal, ground service personnel and vehicles arrive at the aircraft to provide services required before the aircraft can depart from the gate for its next flight. At many airports, loading bridges are not available, and passengers may be required to walk down stairs that are either integral with the aircraft or brought to the aircraft by ground personnel. When the aircraft's engines are used for taxi, ground service personnel and vehicles cannot safely approach the aircraft and passengers cannot board the aircraft until after the engines have been shut down, which adds time to aircraft turnaround.
Typically, before an aircraft is ready to depart a terminal gate, arriving passengers' baggage must be unloaded and departing passengers' baggage must be loaded, the aircraft must be fueled, lavatories may be cleaned and waste water removed, potable water may be supplied to the aircraft, trash may be removed, catering supplies may be delivered, and other services may be performed or provided. The level of services performed or provided depends, in part, on the airline operating the aircraft. A low cost carrier flying commuters between cities may not perform or provide all of the foregoing kinds of services every time the aircraft turns around. An airline that flies long distance international flights is more likely to perform or provide all of them.
The airline industry has recognized the importance of efficiently unloading and loading passengers and providing the requisite servicing of aircraft so aircraft can be turned around as quickly as possible to maintain an airline's flight schedule and achieve the highest aircraft utilization possible. Moreover, an airline's potential profits may be increased the less time an aircraft is on the ground and the more time it is in flight. It has been estimated by one source that every saved minute of a turnaround has the potential to save about US$1 million per aircraft per year, depending on the number of flights and flight days an airline operates.
To increase the efficiency with which passengers can be moved out of and into aircraft, especially very large aircraft that have multiple entrances and two passenger levels, some airport terminal gates have two loading bridges available for such aircraft that can be extended either horizontally or vertically to service aircraft using two different doors. In one arrangement, an “over-the-wing” bridge is designed to be connected to an aircraft's rear door while a conventional loading bridge is connected to the aft door to provide two passenger loading bridges for Airbus 319-321 and Boeing 737 aircraft. Such an arrangement is described in U.S. Pat. No. 7,039,978 to Hutton and is also available from FMT Aircraft Gate Support Systems of Sweden. This type of passenger loading bridge must be designed to clear the aircraft wing height, also allowing for the height of winglets on the tips of most aircraft wings. Maneuvering an over-the-wing loading bridge into place can pose challenges.
Another type of dual passenger loading bridge system is described and shown in U.S. Pat. Nos. 7,275,715 and 7,614,585, assigned to Boeing. This complex system, which is designed to be used with an aircraft parked perpendicular to a terminal building in a “nose-in” orientation, may also include structure for handling baggage and cargo and for providing some aircraft utilities. The Boeing system has an arrangement of lateral bridge extensions that are required to connect one or more main bridge sections to doors on one or both sides of the aircraft. Although the intent of a dual passenger loading system, such as the Boeing system and the over-the-wing type of system, is to allow faster passenger egress and ingress, that objective has not always been achieved. It has been observed that the when dual loading bridges are available, the practice has been to use one loading bridge for first and business class passengers and the other for economy class passengers.
The use of multiple passenger loading bridges to enable connections with aircraft forward and rear doors is shown in U.S. Pat. No. 3,916,588 by Magill. Magill employs mobile, self-propelled passenger loading bridges that may be connected to a permanent passenger loading bridges from an adjacent gate to extend distances required to connect to an aircraft's rear door. Not only does this arrangement limit use of the adjacent gate by another aircraft, but it also is likely to block a significant area of the ramp around the aircraft to which it is connected.
For a number of years, aircraft utilities have been attached to passenger loading bridges and connected to aircraft to supply, for example, electric power, temperature and humidity-conditioned air, and compressed air to an aircraft at a gate during the turnaround process. In U.S. Pat. No. 3,521,316, Adams et al describes providing these utilities to an aircraft concurrently with passenger boarding. The service transport unit described by McEntire et al in U.S. Pat. No. 5,149,017 includes a utility bundle attached to and designed to extend and retract with a passenger loading bridge, and the loading bridge-mounted heat exchanger with extensible supply and return lines described by Shepheard in U.S. Pat. No. 4,620,339 provides utilities to a parked aircraft. The foregoing arrangements avoid the need for providing such aircraft services by separate conduits or connections not associated with a landing bridge and reduce the numbers of such structures in a terminal gate area.
U.S. Pat. No. 5,505,237 to Magne discloses a partially or completely automated aircraft refueling installation integrated into a passenger loading bridge to eliminate or reduce the need for fuel vehicles in a gate area. Improving aircraft gate turnaround by increasing the efficiency of gate services is not a stated goal of the systems in this or in the aforementioned patents.
The loading bridge arrangements described above, whether or not aircraft utilities are connected with the loading bridge, are all premised on providing connections with aircraft that are parked in a “nose-in” or slightly angled orientation relative to an airport terminal building so that the longest axial dimension of the aircraft is perpendicular or somewhat angled with respect to the terminal building. Consequently, passenger loading bridges are presently constructed to that they can be extended between the terminal and the aircraft at an angle that will provide an effective connection when an aircraft is parked at a gate. Many passenger loading bridges have rotundas or the like that can rotate and thus facilitate the connection between a loading bridge and an aircraft door, but alignment may still pose challenges. When aircraft are able to park so that the longest axial dimension is not perpendicular, but parallel, to a terminal building, extension and alignment of passenger loading bridges with aircraft doors is much simplified.
The advantages of moving an aircraft into a parking location parallel to a terminal and connecting a parallel parked aircraft to a terminal building were acknowledged by Hutton in U.S. Pat. No. 7,039,978. Hutton further emphasized very significant disadvantages presented by parallel parking an aircraft. It was noted that, not only do the aircraft maneuvers for parallel parking required greater terminal façade length than the nose-in orientation, but that departure of an aircraft from a parked parallel position requires substantial engine thrust to start and turn the aircraft. Additionally, engine exhaust from a turning aircraft is directed toward a terminal building, ground equipment, and personnel, disrupting ground operation activities. In U.S. Pat. No. 3,184,772, Moore et al describe and show an aircraft parked parallel to a terminal building with dual passenger loading bridges designed to provide connections to forward and aft aircraft doors, which facilitates alignment of the loading bridges with the aircraft. This arrangement, however, does not address the other stated disadvantages associated with parking an aircraft parallel to a terminal building.
A need exists, therefore, for a system and method for improving efficiency of aircraft gate services and turnaround. A need further exists for improved multiple function passenger loading bridges designed to be connected efficiently to multiple doors in an aircraft driven into a parking orientation parallel to an airport terminal building by an engines-off electric taxi system to provide efficient passenger egress and ingress simultaneously with aircraft gate servicing, particularly baggage handling and transfer services, so that baggage may be transferred directly from an aircraft to an airport baggage handling system.